1. Field of Invention
The present invention relates to a holding device, and more particularly a tool holding device for a road planer.
2. Description of Related Art
A cutter holder and a tool holding device for the road planer are shown in EP 1761682 and US 2006/0119165. The cutter holder and the tool holding device respectively include a base and a block wherein the base is welded on the peripheral surface of the working member (ex. roller) and the block is secured on the base through a fastening member to receive a tool (such as a chisel). The tool received in the block is located along a tangent of the roller to dig into the earth for planning, excavating or milling operation.
When the road planer works, the tool bit is forced to drill and excavate as the roller rotates such that the processed material (such as concrete and asphalt) coated on the road surface can be removed. In addition, the tough processed material shortens the lifetime of the tool and results in frequent replacements of the tool. However, the counterforce resulting from the operation is stressed on both the base and the block such that extensive replacement and large costs arise because of the inferior tightness between the base and the block.
Therefore, raising the connection strength of the tool holding device to overcome the tough processed material is important. Because the counterforce resulting from the operation of the road planer is stressed on both the base and the block, the block may wear out or even break after a long operation period. As a result, reinforcing the connection strength between the base and the block of the tool holding device, extending the use period, and reducing cost is the aim of the present invention.